Whether you plan to formula feed your baby from the start, want to supplement your breast milk with formula, or are switching from breast milk to formula, you probably have questions.

Here are answers to some common questions about formula feeding.

What Supplies Do I Need?

Start with the basics:

• formula
• water (tap water is fine, but use bottled if you are concerned about water safety)
• bottles
• nipples

Keep burp cloths and a bottle/nipple brush handy.

You don’t need a bottle sterilizer, but do sterilize bottles and nipples by boiling them for 5 minutes before the first use.

What Kind of Bottle Should I Use?

Bottles come in different shapes and sizes. They can be made of glass, plastic, silicone, or stainless steel. Here are some differences:

Plastic bottles are now "BPA-free"— meaning they don't contain the chemical bisphenol A (BPA). This chemical may be harmful and is found in some plastics, but is banned from baby bottles. Years ago, some plastic baby bottles had BPA in them, but none do now.

Glass bottles. Glass bottles can cause injury if broken, but silicone sleeves make them easier to grip and help prevent breaks.

Silicone bottles and stainless steel bottles are newer options. They are unbreakable but tend to be more expensive than plastic or glass.

Some babies do better with certain bottle shapes, vented bottles, or bottles with liners on the inside. You may need to try a few kinds before you find what works best for you and your baby.

To get you through the first week or so, be sure to have enough formula, water, bottles, and nipples.

Over time, you may want to buy more or different kinds of bottles. You also may find it's worth getting other supplies, like a bottle drying rack or special dishwasher basket.

What Kind of Nipple Should I Use?

Nipples can be made of silicone (clear) or latex (brown) with many different shapes. The varieties include standard or traditional nipples, orthodontic nipples, wide-based nipples, and flat-top nipples. Use whatever type your baby seems to prefer.

Nipples also often come in different numbers, "stages," or "flow rates" to reflect the size of the nipple's hole, which affects the flow (i.e., slow, medium, or fast) of formula or breast milk. The holes get bigger as babies get older and are ready to handle faster flows of milk. Flows that are too fast can make younger babies gag by giving them more milk than they can handle. Slower flows may frustrate some babies and make them suck harder and gulp too much air.

Start your newborn on the slowest flow nipple. As your baby gets older, you can increase the flow if you want to. Some babies may be content throughout infancy to use the same kind and size of nipple. If your baby seems fussy or frustrated with the nipple, try a different kind (like one with a larger hole) to see if it makes a difference.

How Often Should Nipples Be Replaced?

That depends on how the nipples you use hold up to cleaning and everyday use. Check them regularly for signs of wear and replace them about every 2 months or sooner if you notice tears or damage.

What Type of Formula Should I Use?

Many different formulas are available these days. Ask your doctor which kind is best for your baby.

Do not try to make your own formula at home. Online recipes may look healthy and promise to be nutritionally complete, but they can have too little — or too much — of important nutrients and cause serious health problems for your baby.

There are many different brands of formula, and all that are made in the United States (name brands, store brands, and generic) must meet strict nutrition and safety standards.

Formula types include:

• cow's milk-based formulas. Most formulas are made from cow's milk. These formulas have added iron, which babies need. Use only iron-fortified formula, unless your doctor advises you not to.
• soy-based formulas. These are for babies born with congenital lactase deficiency or galactosemia. This type of formula is also used by parents who do not want their babies to eat animal protein. Give only iron-fortified soy formula, unless your doctor says otherwise. (Many babies who are allergic to cow's milk also are allergic to the protein in soy formulas, so soy-based formulas generally don't help with milk-protein allergies.)
• hypoallergenic formulas for babies who can't tolerate cow’s milk or soy formulas, like those with allergies to milk or soy proteins. The proteins in hypoallergenic formulas are broken down so they are easier to digest.
• specialized formulas. These are designed for premature babies.

How Do I Prepare Formula?

Formula comes in three basic forms:

• powders that require mixing with water and cost the least
• concentrates, which are liquids that require diluting with water
• ready-to-use (or ready-to-feed) liquids that can be poured right into bottles. These are the most expensive but are convenient if you're traveling or can't get to a clean water supply.

Carefully follow directions on the label when preparing formula. Do not add more water than directed.

Whatever formula you choose, check the expiration date on all cans and bottles of formula, and don't use formula from leaky, dented, or otherwise damaged containers. Do not water-down formula — this is dangerous, as it reduces the amount of nutrients in each bottle.

Formula Can Be Pricey. How Can I Save Money?

Shop around for the best deals on the formula you've chosen:

• Take advantage of the free samples and coupons sent to you in the first few months after your baby is born.
• Clip coupons and sign up for online coupon clubs and apps that let you print and save coupons.
• Sign up for formula companies' clubs and special programs (through the mail or online) that may offer discounts, coupons, and/or free formula and other products.
• Compare prices on formula at online retailers. Some online stores have special "mom" clubs that let you save regularly on some products every month.
• Check for specials at your grocery store, baby store retailer, or local wholesale/bulk items store.

What if I Need Help Paying for Formula?

If you can't afford formula, talk to your doctor or call 211 to help you find local resources. You and your family may be eligible for assistance through:

• Special Supplemental Nutrition Program for Women, Infants, and Children (WIC)
• Supplemental Nutrition Assistance Program (SNAP)
• Temporary Assistance for Needy Families